Apparatus for developing photographic films



March 30, 1937.

H. A. WINDISCH APPARATUS FOR DEVELOPING PHOTOGRAPHIC FILMS Filed Oct. 9,1935 3 Sheets-Sheet l March 30, 1937. H. A. WINDISCH APPARATUS FORDEVELOPING PHOTOGRAPHIC FILMS Filed Oct. 9, 1955 3 Sheets-Sheet 2 March30, 1937' H. A. 'WINDISCH Y 72,075,637

'API ARATUS FOR DEVELOPING PHOTQGRAPHIC FILMS Filed Oct. 9, 1935 5Sheets-She et a frwezuori- Hamid :4. Wm 0/2 Patented Mar. 30, 1937UNITED STATES PATENT OFFICE APPARATUS FOR DEVELOPING PHOTO- GRAPHICFILMS 9 Claims.

This invention relates to improvements in apparatus for developingphotographic films. The invention has for its principal object theprovision of novel apparatus in which the entire developing process,inclusive of the steps of immersing the film in the developing solution,the subsequent washing of the film to free it from the developer,

and the fixing and final washing operations, may be conducted under fulldaylight conditions and without recourse to a dark room.

To this general end, another and specific object of the invention is toprovide a light-proof tank equipped with novel means for unwinding theundeveloped filin from the roll and for guiding the film into anadequately supported position within the tank in which all parts thereofare exposed for contact with the developing liquids, said meansproviding for exclusion from active contact with said liquids of thebacking paper with which a the film is conventionally provided, as wellas any other foreign materials which might adversely affect the film.

A further object of the invention is to provide novel apparatus of thecharacter set forth permitting inspection of the film at any time duringthe developing, fixing or washing operations.

Still another object of the invention is to provide apparatus of thestated character in which all working parts are removable to facilitatem cleaning, and in which all surfaces exposed to the developingchemicals are available for cleaning and drying.

A further object of the invention is to provide in apparatus of thestated character novel means 53 for locating the film in a fixedposition in which it is maintained at all times during the developingprocess.

Still another object of the invention is toprovide apparatus of thestated character which shall m be adjustable and readily adaptable todifferent sizes of film. thereby making possible the use of a singletank or container for films of various sizes.

A still further object of the invention is to provide a developing tankprovided with novel means for automatically regulating the depth of theliquids in the tank and for preventing the trapping of air in the tankwhen the liquids are admitted.

The invention further contemplates the provi- 50 sion of a portabledevice of the stated character of relatively inexpensive constructionthat may be built economically of any suitable acid-resisting materialand which can be used under any light conditions and at any place wherewater is available.

The foregoing and further objects hereinafter appearing are attained bymeans of the novel devices illustrated in the attached drawings,wherein:

Figure 1 is a view in perspective of the assembled tank;

Fig. 2 is a plan view of the tank with the cover removed;

Fig. 3 is a section on the line 3--3, Fig. 2;

Figs. 4, 5 and 6 are views in perspective of elements of the devicenormally occupying positions within the tank as illustrated in Figs. 2and 3 and removable from the tank for cleansing;

Fig. 7 is a view in perspective of one of the elements of the membersshown in Fig. 5, and

Figs. 8 and 9 are, respectively, diagrammatic and detached perspectiveviews illustrating the operation of the device.

With reference to Figs. 1 to 3 of the drawings, apparatus made inaccordance with my invention comprises a tank consisting primarily of abase or body portion l and a lid or cover 2, the latter being removable.At one end, as shown at the right of Figs. 2 and 3, the body I isprovided with an intake spout 3 the lower end of which adjoins thebottom of the tank and which extends upwardly at an angle away from theend wall 4. This same end of the tank is provided with an overflow duct5 the inner end of which communicates with the bottom of an overflowchamber 6 in the interior of the tank and which extends downwardly at anangle from the end Wall as illustrated. A third and normally closed duct1 extends from the bottom of the end wall 4 and serves as a dischargeport from which the liquid contents of the tank may be readily removed,the position of this duct 1 being indicated in broken lines in Fig. 3.

In the interior of the tank and at the opposite end is a curved baffle 8which terminates at its inner and lower end in a vertical section 9 andwhose outer and upper end lies flush with the bottom of a slotted port II, which as shown in Fig. 1 extends across substantially the entirewidth of the tank; and the adjoining end wall of the body I is providedwith a slide [2 which may be elevated through the medium of a lip l3from the normal depressed position in which it is shown in Fig. 3 tocover the port ll, this slide also having the function of a clamp, ashereinafter more fully described. It will be noted that thecorresponding end wall I4 of the cover 2 is so formed as to leave theslot ll exposed when the cover is in place, as shown in Fig. 1. With theexception of two ribs IS in the form in the present instance of rodssecured in vertical position to the opposite side walls of the body I ofthe tank adjacent the lower end of the baille 8, the aforedescribedelements constitute the fixed or permanently attached portions of thetank proper.

Adapted to fit within the body I of the tank in a position overlying thebafiie 3 is a member l5 shown in perspective in Fig. 4. This membercomprises side walls ll which in assembly and as shown in Fig. 2 liecontiguous to the side walls of the tank body i, these Walls beingconnected by a continuous web l8 shaped as best shown in Fig. 3 toconform at the bottom with the curved baffle 8 upon which it normallyrests. The upper surface of the web i8 forms a smooth curve terminatingat one end at or adjacent to the port ll; while the inner portion of theweb is shaped to provide a cavity 19 which in assembly is occupied by afilm roll holder 2i shown in perspective in Fig. 5 and hereinafterdescribed in detail. The member it also comprises a curved web 22 whichextends as shown in Figs. 2 and 4 between the side walls ll, this weblying in spaced relation to the upper portion of the web It and being iso arranged that its outer edge in assembly registers with the upperedge of the slot l l, as shown in Fig. 3. The inner ends of the walls l!are provided on the inner surfaces with ribs 23, which in effect definethe inner vertical edges of the walls and function as hereinafterdescribed to locate and partially support the film roll holder 2!. Themember l5 also comprises a transverse rod 24 which is supported in andextends between the side walls 4 i, this rod as hereinafter describedfunctioning as a guide for the film fed into the tank from the film rollsupported in the holder 2 i.

v The holder 2 i, as shown in Figs. 2, 3 and 5, consists of a plate 25the lower reduced portion of which is bent into the form of a bead orcurved apron 25. The plate 25 supports a fixed bracket 21 provided withan inwardly projecting pin 28 which constitutes a journal for one end ofthe film spool. The opposite end of the film spool is journaled on asimilar pin shown projecting from an oppositely arranged bracket 29, seeFig.

7, which is slidably mounted on the plate 25 for adjustment to and fromthe bracket 28. In the present instance, the base portion SI of thebracket 29 is extended and is provided with a slot 32, the base portion3i being confined against the side of the plate 25 by means of aretaining plate 33 secured in spaced relation to the plate 25 by meansof rivets or other suitable elements 34 which extend through the slot 32of the bracket 29 whereby the said bracket is supported for itsrectilinear adjustment movement. The holder 2i also comprises a leafspring 35 which is secured to the base plate 25 and extends inwardlybetween the spool-supporting brackets 21 and 29 and which as shown inFig. 8 is adapted to exert pressure against the side of the film roll35. In assembly, the side edges of the plate 25 are slidably supportedbetween the ribs 23 of the member l6 and the ribs !5 of the tank body,and a transverse rib 3? on the plate 25 rests in assembly and as shownin Fig. 3 upon the upper ends of the ribs [5 whereby the holder 2! ispositioned properly within the tank body. It will be noted that both themember l5 and the holder 21 may readily be removed from the tank bodywhen required.

The device further comprises a skeleton frame or rack 38 shown inperspective in Fig. 6. This rack, which may readily be fabricated fromwire of suitable gauge, comprises longitudinal base elements or rods 39,39, the terminal ends 4| of which are turned down to form feet, which inassembly and as shown in Fig. 3 rest upon the bottom of the tank body Iand support the frame 38 in an elevated position in the bottom of thetank. The rods 39 are connected by transverse rods 42 and 43. The rack38 further comprises upper longitudinal rods 44, 44 which over theirgreater length extend above and in parallel alignment with the lowerrods 39. At one end of the frame the rods 44 are offset outwardly, asindicated at 45, and these offset terminal ends are provided withbearings 45 in which is journaled a reel 47. This reel in the presentinstance comprises heads 48 in the form of disks having trunnions 49which are journaled in the bearings 46, and an annular series of rods 51extends between the disks 48 to form the working body of the reel. Theupper rods 44 of the frame are connected by means of transverse rods 52,52, which also function as a support for the film, as hereinafterdescribed.

Extending upwardly above the upper rods 44 and adjacent the oppositeends of the rack are loops 53, 53 which in assembly and as shown in Fig.3 extend substantially to the top of the body I of the tank and whichprovide readily available means for inserting and withdrawing the rackfrom the tank. That one of the loops 53 which adjoins the end of therack in which the reel 4i is mounted also forms a support for the upperends of two curved rods 54, 54, these rods extending downwardly betweenthe oiTset ends 45 of the upper longitudinal rods 44 and being suitablysecured at their lower ends to the inner sides of the lower longitudinalrods 39, as best shown in Fig. 3. The rods 54 form a support for anapron or guard plate 55 which embraces the outer side of the reel 41.

As shown in Fig. 2, the rack 38 is adapted to rest in the bottom of thetank and extends from the right-hand end of the tank, as viewed in thesaid drawings, to a point adjoining the inner end of the baffle 8 and ofthe member 16. The upper longitudinal rods 44 of the rack occupy a planesomewhat above the lower inner ends of the member 15, and the adjoiningends of these longitudinal rods are curved down, as indicated at 56 inFig. 3, to a point adjoining the inner lower end of the continuous webl8. It will be apparent that when the tank is filled with liquid to apoint determined by the position of the overflow chamber 6, the entirerack, with the exception of the upper ends of the loops 53, will beimmersed. The normal position of the rack transversely of the tank isdetermined by the offset ends 45 of the rods 44 and by a rod 58 at theother end of the rack which projects at both ends into proximity to theside walls of the tank, see Figs. 2 and 6.

In the use of the apparatus for developing photographic films theprocedure is as follows: As illustrated in Fig. 9, the backing strip 57of the film roll is unwound from the spool to an extent exposing thefree end of the gummed paper leader 58a conventionally provided for thefilm strip 58. To this free end is attached, preferably by means of thesaid adhesive. a guide strip 59. This can be done under daylightconditions without danger of adversely affecting the picture-containingportions of the film, since these portions remain covered by the backingpaper. With the film spool inserted in the holder 2| as previouslydescribed and as illustrated in Fig. 2, and with the spring engaging thefilm roll and preventing the film from loosening on the spool, the freeend of the backing paper 51 is passed over the top of the web l8 andthrough the port I l. The guide strip 59 is passed downwardly under therod 24 and bead 26, longitudinally over the transverse bars 52 at thetop of the rack 33, around the reel ll, and back under the transversebars 52 to the opposite end of the rack. At this point, it is passedbetween the baiiie 8 and the web 98 of the member it to and through theport I l The cover 2 of the tank may now be placed in position toexclude all light from the interior of the tank. Entrance of light intothe tank through the port II is effectively excluded by the webs I8 and22 of the member 16 in conjunction with the curved battle 8. As regardsthe ducts 3, 5 and I, it is proposed to employ on each of these ductsshort sections of rubber tubing which form efiective traps preventingentrance of light to the interior of the tank through these openings,although obviously the ducts could be formed to provide in themselvesefiective light traps. The free ends of the backing paper 51 and theguide strip 59 which project from the port ii are pulled away from theend of the tank, with the result that the film is unwound from its spooland drawn into a looped position on the rack 38 and around the reel 41.This operation by reason of the proximity of the two strips can beconducted with one hand, the strips being withdrawn simultaneously.During this operation, both the film and the backing strips aremaintained under tension, and there is no possibility for the strips tobuckle and jam. When the film has been entirely unwound from the spool,the slide I2 may be elevated to close the port I I and also to clamp thebacking paper and the guide strip tightly in position, thereby givingassurance that the film is held fixed in its position upon the rack 38.Preferably the parts are so proportioned that when the film strip isentirely transferred from the spool to the rack, the paper leader 58awill lie between the bafile a 8 and web l8, while the guide strip 59 isentirely withdrawn from the tank.

Sufficient developer solution is passed into the tank through the duct 3to entirely cover the film supported as previously described upon therack. This may be a measured quantity of the solution or the solutionmay be passed into the tank until the latter is full, as indicated byflow of solution through the overflow duct 1. In either case, theoverflow provides a free passage of air lrom the tank as the solution isadmitted, thereby preventing trapping of air and formation of air bellsinterfering with the normal developing operation. When the film has beenthus immersed in the solution a sufficient length of time to com pletethe developing operation, the developer solution may be withdrawn fromthe tank through the discharge duct 1 and may be collected for furtheruse in subsequent developing operations. Water is then flowed throughthe intake 3 and may be continuously circulated through the tank, fromwhich it passes through the overflow until the film is completely freefrom traces of the developer solution, after which the cleansing watermay be removed from the tank through the discharge duct I, and may bereplaced in obvious manner by a fixing solution, which with theexception of the final washing completes the developing process.

During this entire process, the film has been maintained in completedarkness, so that the ap-- paratus is adapted for daylight developmentof the panchromatic and supersensitive films now in common use. Theapparatus, however, by simple removal of the cover, provides forinspection of the film at any time during the developing process byelevating the rack. It will be noted that the apparatus provides for thepractical exclusion of the backing paper and the guide and leader stripsfrom active contact with the liquid-treating mediums. The backing stripin particular is maintained at all times out of contact with thesolutions, this being important by reason of the fact that frequentlycontact of the backing paper with the developer solution results in astaining of the solution and resultant damage to the film. The guidestrip also is effectively excluded from contact with the solutions, inthat the latter is removed from the space between the bafile 8 and theweb it? in which the inner end of the strip may lie. Where the length ofthe film is such that a portion of the guide strip remains in the tankproper, a mate rial may be used for the strip which is inert to thedeveloping chemicals, so that there is no danger of damage to the filmfrom this source.

As previously set forth, a desirable feature of the apparatus resides inthe fact that the film during the developing process is maintained in adefinite fixed position within the tank in which all parts thereof areuniformly exposed to the developing chemicals. In this position, no partof the film can come in contact with another part. By making the filmspool holder 2| adjustable, the device is adapted for different sizes offilm. The construction is simple and relatively inexpensive and providesfor the removal of all of the working parts for thorough cleaning afteruse. So far as I am aware, the apparatus is the first that provides forthe complete processing of a photographic film including treatment ofthe film with both the developing medium and the fixing medium and theintermediate and subsequent washing operations by a continuous processand without recourse to a dark room or the equivalent.

I claim:

1. In photographic developing apparatus for roll films, the combinationwith a light-proof tank having a detachable cover, of a rack sepa ratefrom the tank and from said cover adapted to support the film. strip insubstantially horizontal position in the bottom of the tank andremovable from the latter, means providing for transfer within the tankof the film strip from the roll to the rack and for simultaneousseparation from said film of its hacking strip, and means operativewhile the tank is substantially in normal position for admitting anddischarging liquids to and from the tank while the said cover is inposition.

2. In photographic developing apparatus for roll films, the combinationwith a light-proof tank having a detachable cover, of a support for saidroll mounted in the upper part of said tank, a rack adapted to supportthe film strip in substantially fixed position in the bottom of saidtank, means providing for transfer within the tank of the film stripfrom the roll to the rack and for simultaneous separation from said film01: its backing strip, means for admitting a liquid to the tank and fordischarging said liquid while the cover is in position, and overflowmeans adapted to limit the height of the liquid within the tank to alevel below the top of said roll.

3. In photographic developing apparatus for roll films, the combinationwith a light-proof tank having a detachable cover, of means forsupporting said roll in the upper part of said tank, a rack adapted tosupport the film strip in substantially fixed position in the bottom ofthe tank, means providing for transfer within the tank of the film stripfrom the roll to the rack, means for admitting a liquid to the tank andfor discharging said liquid while the cover is in position, overflowmeans for limiting the height of the liquid in the tank to a level belowthe top of said roll, and means operative simultaneously with saidtransfer means for separating 7 the backing strip from said film and forsegregating said backing strip from the portion of said tank below saidoverflow.

4. In photographic developing apparatus for roll films, the combinationwith a light-proof tank comprising a detachable cover, of a horizontalrack for the film strip located in the bott m and at one end of saidtank, a film roll support mounted in the upper portion and at theopposite end of said tank, a slot in the wall of said tank at the endthereof occupied by said roll support,

and removable mean positioned at the slotted end of said tank forproviding light-excluding channels extending from said slot to the rollfilm support and to the adjoining end of said rack respectively.

5. In photographic developin apparatus for roll films, the combinationwith a light-proof tank comprising a detachable cover, of a horizontalrack for the film strip located in the bottom and at one end of saidtank, a film roll support mounted in the upper portion and at theopposite end of said tank, a slot in the wall of said tank at the endthereof occupied by said roll support, a wall providing an elongatedsurface extending from the slot to the adjoining end of the rack, and aremovable element having a lower surface conforming to and normallyresting upon said elongated surface and having an extended upper surfaceforming a guide extending from said slot toward the roll support.

6. In photographic developing apparatus for roll films, the combinationwith a light-proof tank comprising a detachable cover and having atransverse slot adjacent the top of one end wall, means for supporting afilm roll in the upper part of the tank adjacent said slotted end wall,a wall element extending downwardly from the slot and toward theopposite end of the tank and providing an extended guide surfaceterminating in the lower part of the tank,

a mem er having a lower surface conforming to and normally resting uponsaid guide surface and having an upper surface extending from said slottoward the roll support, and a rack in the bottom of the tank comprisingupper and lower film-supporting levels extending from the inner end ofsaid wall element toward the oppo site end of the tank and having towardsaid opposite end means for guiding the film strip from the said upperlevel to the lower level.

'7. In photographic developing apparatus for roll films, the combinationwith a light-proof tank comprising a detachable cover and having atransverse slot adjacent the top of one end wall, means for supporting afilm roll in the upper part of the tank adjacent said slotted end wall,a wall element extending downwardly from the slot and toward theopposite end of the tank and providing an extended guide surfaceterminating in the lower part of the tank, a member having a lowersurface conforming to and normally resting upon said guide surface andhaving an upper surface extending from said slot toward the rollsupport, a rack in the bottom of the comprising upper and lowerfilm-supporting levels extending from the inner end of said wall elementtoward the opposite end of the tank and having toward said opposite endmeans for guiding the film strip from the said upper level to the lowerlevel, means for admitting a liquid to the tank and for discharging saidliquid while the cover is in position, and overflow means located abovethe said upper level of the rack and below the top of a roll mounted insaid roll support.

8. In photographic developing apparatus for roll films, the combinationwith a light-proof tank comprising a detachable cover and having atransverse slot adjacent the top of one end wall, means for supporting afilm roll in the upper part of the tank adjacent said slotted end wall,a. wall element extending downwardly from the slot and toward theopposite end of the tank and providing an extended guide surfaceterminating in the lower part of the tank, a member having a lowersurface conforming to and normally resting upon said guide surface andhaving an upper surface extending from said slot toward the rollsupport, and a rack in the bottom of the tank comprising upper and lowerfilmsupporting levels extending from the inner end of said wall elementtoward the opposite end of the tank and having toward said opposite endmeans for guiding the film strip from the said upper level to the lowerlevel, the rack, the roll holder and said member being removable fromthe tank whereby all surfaces of the apparatus are readily available forcleaning.

9. In photographic developing apparatus for roll films, the combinationwith a light-proof tank having a detachable cover, of a support for saidroll mounted in the upper part of said tank, a rack adapted to supportthe film strip in substantially fixed position in the bottom of saidtank, means providing for transfer within the tank of the film stripfrom the roll to the rack and for simultaneous separation from said filmof its backing strip, means for admitting a liquid to the bottom of thetank and for discharging said liquid while the cover is in position, andmeans providing for free escape of air from the upper portion of saidtank as the liquid is admitted.

HAROLD A. -WINDISCI-I.

